Casse C., Gosset Marielle. (2015). Analysis of hydrological changes and flood increase in Niamey based on the PERSIANN-CDR satellite rainfall estimate and hydrological simulations over the 1983-2013 period. In :
Rogger M. (ed.), Aksoy H. (ed.), Kooy M. (ed.), Schumann A. (ed.), Toth E. (ed.), Chen Y. (ed.), Estupina V.B. (ed.), Bloschl G. (ed.). Changes in flood risk and perception in catchments and cities. Göttingen : Copernicus, p. 117-123. (Proceedings of the International Association of Hydrological Sciences ; 370). IAHS Symposium and General Assembly of the International Union of Geodesy and Geophysics, 26., Prague (CZE), 2015/06/22-07/02. ISSN 2199-899X.
Titre du document
Analysis of hydrological changes and flood increase in Niamey based on the PERSIANN-CDR satellite rainfall estimate and hydrological simulations over the 1983-2013 period
Année de publication
2015
Auteurs
Casse C., Gosset Marielle
In
Rogger M. (ed.), Aksoy H. (ed.), Kooy M. (ed.), Schumann A. (ed.), Toth E. (ed.), Chen Y. (ed.), Estupina V.B. (ed.), Bloschl G. (ed.) Changes in flood risk and perception in catchments and cities
Source
Göttingen : Copernicus, 2015,
p. 117-123 (Proceedings of the International Association of Hydrological Sciences ; 370). ISSN 2199-899X
Colloque
IAHS Symposium and General Assembly of the International Union of Geodesy and Geophysics, 26., Prague (CZE), 2015/06/22-07/02
A dramatic increase in the frequency and intensity of floods due to the Niger River in the city of Niamey (Niger) has been observed in the last decade. Previous studies highlighted the role of the land use changes on the flood increase since 1970s. In the last decade, observations have raised the issue of a possible increase in extreme rainfall in the Sahel, which may have caused the recent and extreme floods in Niamey in 2010, 2012 and 2013. The study focuses on the 125 000 km(2) basin between Ansongo and Niamey. This is the drainage area of the monsoon rainfall that leads to the rapid flow rise occurring between June and October. To understand the possible role of rainfall in flood intensification, satellite rainfall estimate is attractive in a region where the operational gauge network is sparse. This paper analyses the evolution of the Niger hydrograph in Niamey based on discharge observations, hydrological modelling and the satellite product PERSIANN-CDR, over the 1983-2013 period. PERSIANN-CDR is first compared with four other rainfall products. The salient features of the observed changes, i.e. a marked change in the mean decadal hydrograph, is well mimicked by the simulations, implying that rainfall is the first driver to the observed changes. The increase of flooded years over the period is also well reproduced but with some uncertainties in the exact number of flood days per year.
Plan de classement
Hydrologie [062]
Localisation
Fonds IRD [F B010072205]
Identifiant IRD
fdi:010072205
